Over the last several decades an increasing economic base, and increasing urbanization, has caused a corresponding increase in the volume of solid wastes. Additionally, the properties of these wastes have become more varied, and now include a variety of plastic and chemical products containing a diverse cross section of toxic and harmful products. Generally, either burning or embedding (burial) is applied to treat such wastes, resulting in various complicated environmental and regional social problems. This is especially true in treatment by embedding, making the establishment and expansion of landfills increasingly difficult because of higher land utilization rates, and resistance of residents near the landfill. Meanwhile, the problem increases year-by-year with the growing volume of solid waste.
Among solid wastes the amount of plastics has increased dramatically due to the increased use of these substances in home appliances and automobiles, and as a packaging material for fast foods, disposable diapers and medical wastes. Treating these wastes is especially difficult because they are either slow to degrade, or are completely non-biodegradable, thus shortening the life of a landfill. Such biodegradation that does occur creates its own problems through the release of component elements, such as chlorine. Treatment of these wastes by incineration is even more hazardous due to the release of these hazardous materials in the form of air pollution. More recent research has focused on processes for manufacturing biodegradable plastics which can be degraded by microorganisms present in the soil. however, many problems are yet to e solved with respect to the effectiveness of these new plastics.